U.S. patent application number 10/786491 was filed with the patent office on 2004-08-26 for methods for treating ocular neovascular diseases.
Invention is credited to Guyer, David R..
Application Number | 20040167091 10/786491 |
Document ID | / |
Family ID | 23297643 |
Filed Date | 2004-08-26 |
United States Patent
Application |
20040167091 |
Kind Code |
A1 |
Guyer, David R. |
August 26, 2004 |
Methods for treating ocular neovascular diseases
Abstract
Disclosed herein are methods for treating ocular neovascular
disease using anti-VEGF therapy in combination with a second
therapy that inhibits the development of ocular neovascularization
or destroys abnormal blood vessels in the eye, such as photodynamic
therapy.
Inventors: |
Guyer, David R.; (New York,
NY) |
Correspondence
Address: |
EYETECH PHARMACEUTICALS, INC.
3 TIMES SQUARE 12TH FLOOR
NEW YORK
NY
10036
US
|
Family ID: |
23297643 |
Appl. No.: |
10/786491 |
Filed: |
February 25, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10786491 |
Feb 25, 2004 |
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10291091 |
Nov 8, 2002 |
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60332304 |
Nov 9, 2001 |
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Current U.S.
Class: |
514/44A ;
424/145.1 |
Current CPC
Class: |
C12Q 1/6886 20130101;
A61K 31/7088 20130101; A61K 31/409 20130101; A61K 31/765 20130101;
A61P 43/00 20180101; A61P 27/02 20180101; A61K 31/555 20130101 |
Class at
Publication: |
514/044 ;
424/145.1 |
International
Class: |
A61K 039/395; A61K
048/00 |
Claims
We claim:
1. A method for treating an ocular neovascular disease in a
patient, said method comprising the steps of administering to said
patient an effective amount of an agent that inhibits the
development of ocular neovascularization, said agent being provided
in a controlled release formulation comprising a biocompatible,
biodegradable polymer selected from the group consisting of lactide
polymers, lactide/glycolide copolymers, or
polyoxyethylene-polyoxypropylene copolymers.
2. The method of claim 1, wherein said neovascular disease is
selected from the group consisting of ischemic retinopathy,
intraocular neovascularization, age-related macular degeneration,
corneal neovascularization, retinal neovascularization, choroidal
neovascularization, diabetic macular edema, diabetic retina
ischemia, diabetic retinal edema, and proliferative diabetic
retinopathy.
3. The method of claim 1, wherein said agent comprises an anti-VEGF
agent.
4. The method of claim 3, wherein the anti-VEGF agent is selected
from the group consisting of aptamers, antibodies, antibody
fragments, and antisense molecules.
5. The method of claim 4, wherein said neovascular disease is
age-related macular degeneration.
6. The method of claim 4, wherein said neovascular disease is
proliferative diabetic retinopathy.
7. The method of claim 5, wherein said anti-VEGF agent comprises an
aptamer.
8. The method of claim 7, wherein the aptamer comprises a nucleic
acid ligand to vascular endothelial growth factor (VEGF).
9. The method of claim 8, wherein said VEGF nucleic acid ligand
comprises ribonucleic acid.
10. The method of claim 9, wherein said VEGF nucleic acid ligand
comprises deoxyribonucleic acid.
11. The method of claim 8, wherein said VEGF nucleic acid ligand
comprises modified nucleotides.
12. The method of claim 11, wherein said VEGF nucleic acid ligand
comprises 2'F-modified nucleotides.
13. The method of claim 8, wherein said VEGF nucleic acid ligand
comprises a polyalkylene glycol.
14. The method of claim 13, wherein said polyalkylene glycol is
polyethylene glycol (PEG).
15. The method of claim 11, wherein said VEGF nucleic acid ligand
comprises 2'-O-methyl (2'-OMe) modified nucleotides.
16. The method of claim 7, wherein the aptamer comprises pegaptanib
sodium.
17. The method of claim 16, wherein said anti-VEGF aptamer is
delivered to the eye by transcleral diffusion.
18. A method for treating age-related macular degeneration in a
patient, said method comprising the steps of administering to said
patient an effective amount of an anti-VEGF agent that inhibits the
development of ocular neovascularization, said agent being provided
in a controlled release formulation comprising a biocompatible,
biodegradable polymer selected from the group consisting of lactide
polymers, lactide/glycolide copolymers, or
polyoxyethylene-polyoxypropylene copolymers.
19. The method of claim 18, wherein the agent comprises an
aptamer.
20. The method of claim 19 wherein the aptamer comprises pegatanib
sodium.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 10/291,091, filed Nov. 8, 2002, which claims priority to U.S.
Provisional Application Serial No. 60/332,304, filed on Nov. 9,
2001.
FIELD OF THE INVENTION
[0002] The invention relates to methods for treating ocular
neovascularization using agents that inhibit VEGF.
BACKGROUND OF THE INVENTION
[0003] Angiogenesis, or abnormal blood vessel growth, has been
implicated as an important cause of pathological states in many
areas of medicine, including ophthalmology, cancer, and
rheumatology. For example, the exudative or neovascular form of
age-related macular degeneration (AMD) is a leading cause of
blindness in the elderly. There is currently no standard and
effective therapy for the treatment of exudative ADM in most
patients. Thermal laser photocoagulation and photodynamic therapy
(PDT) have been shown to be beneficial for subgroups of such
patients. However, only a fraction of eyes meet the eligibility
criteria for such therapeutic interventions and those treated have
a high recurrence rate.
[0004] Recent pre-clinical studies have suggested that
pharmacological intervention or anti-angiogenesis therapy may be
useful to treat various forms of ocular neovascularization, such as
choroidal neovascularization (CNV). Much of this work has focused
on blocking vascular endothelial growth factor (VEGF), which has
been implicated in the pathogenesis of CNV secondary to AMD and the
pathogenesis of diabetic retinopathy. VEGF is an important cytokine
growth factor involved in angiogenesis and appears to play a
critical role in the development of ocular neovascularization.
Human studies have shown that high concentrations of VEGF are
present in the vitreous in angiogenic retinal disorders but not in
inactive or non-neovascularization disease states. Excised human
CNV after experimental submacular surgery have also shown high VEGF
levels. Other studies have shown regression or prevention of
neovascularization in multiple vascular beds in several animal
models, using various types of anti-VEGF agents, including antibody
fragments. Thus, anti-VEGF therapy is a promising new treatment for
AMD, diabetic retinopathy, and related disorders.
[0005] In addition to a potential anti-angiogenic effect, anti-VEGF
therapy may be useful as an anti-permeability agent. VEGF was
initially referred to as vascular permeability factor due to its
potent ability to induce leakage from blood vessels. Recent
research has shown that VEGF may be important in causing vessel
leakage in diabetic retinopathy and that the diabetes-induced
blood-retinal barrier breakdown can be dose-dependently inhibited
with anti-VEGF therapy. Anti-VEGF therapy may, therefore, represent
a two-prong attack on CNV via its anti-angiogenic and
anti-permeability properties.
[0006] Existing methods for treating ocular neovascular disease are
in need of improvement in their ability to inhibit or eliminate
various forms of neovascularization, including choroidal
neovascularization secondary to AMD and diabetic retinopathy.
Furthermore, there is a continuing and significant need to identify
new therapies to treat ocular neovascularization. The present
invention fulfills these needs and further provides other related
advantages.
SUMMARY OF THE INVENTION
[0007] We have conducted clinical trials of an anti-VEGF aptamer
with and without photodynamic therapy in patients with subfoveal
choroidal neovascularization secondary to age-related macular
degeneration to determine the safety profile of multiple injection
therapy. We found that anti-VEGF therapy with or without
photodynamic therapy (PDT) was both safe and effective in treating
patients suffering from AMD and related disorders. Most patients
receiving the anti-VEGF aptamer exhibited stable or improved vision
three months after treatment. Those receiving anti-VEGF therapy in
combination with PDT exhibited the most dramatic improvement in
vision. Thus, anti-VEGF therapy, either alone or in conjunction
with angiogenic therapies, is clearly a promising treatment for
various forms of ocular neovascularization, including AMD and
diabetic retinopathy.
[0008] Accordingly, the present invention features a method for
treating a patient suffering from an ocular neovascular disease,
which method includes the following steps: (a) administering to the
patient an effective amount of an anti-VEGF aptamer; and (b)
providing the patient with phototherapy, such as photodynamic
therapy or thermal laser photocoagulation.
[0009] In one embodiment of the invention, the photodynamic therapy
(PDT) includes the steps of: (i) delivering a photosensitizer to
the eye tissue of a patient; and (ii) exposing the photosensitizer
to light having a wavelength absorbed by the photosensitizer for a
time and at an intensity sufficient to inhibit neovascularization
in the patient's eye tissue. A variety of photosensitizers may be
used, including but not limited to, benzoporphyrin derivatives
(BPD), monoaspartyl chlorin e6, zinc phthalocyanine, tin
etiopurpurin, tetrahydroxy tetraphenylporphyrin, and porfimer
sodium (PHOTOFRIN.RTM.), and green porphyrins.
[0010] In a related aspect, the present invention provides a method
for treating an ocular neovascular disease in a patient, which
method involves administering to the patient: (a) an effective
amount of an anti-VEGFaptamer; and (b) a second compound capable of
diminishing or preventing the development of unwanted
neovasculature. The anti-VEGF agents or other compounds that may be
combined with anti-VEGF aptamers include, but are not limited to:
antibodies or antibody fragments specific to VEGF; antibodies
specific to VEGF receptors; compounds that inhibit, regulate,
and/or modulate tyrosine kinase signal transduction; VEGF
polypepides; oligonucleotides that inhibit VEGF expression at the
nucleic acid level, for example antisense RNAs; retinoids; growth
factor-containing compositions; antibodies that bind to collagens;
and various organic compounds and other agents with angiogenesis
inhibiting activity.
[0011] In a preferred embodiment of the invention, the anti-VEGF
agent is a nucleic acid ligand to vascular endothelial growth
factor (VEGF). The VEGF nucleic acid ligand may include ribonucleic
acid, deoxyribonucleic acid, and/or modified nucleotides. In
particularly preferred embodiments, the VEGF nucleic acid ligand
includes 2'F-modified nucleotides, 2'-O-methyl (2'-OMe) modified
nucleotides, and/or a polyalkylene glycol, such as polyethylene
glycol (PEG). In some embodiments, the VEGF nucleic acid ligand is
modified with a moiety, for example a phosphorothioate, that
decreases the activity of endonucleases or exonucleases on the
nucleic acid ligand relative to the unmodified nucleic acid ligand,
without adversely affecting the binding affinity of the ligand.
[0012] In yet another aspect, the invention provides a method for
treating an ocular neovascular disease in a patient, which method
involves the steps of: (a) administering to the patient an
effective amount of an agent that inhibits the development of
ocular neovascularization, for example, an anti-VEGFaptamer; and
(b) providing the patient with a therapy that destroys abnormal
blood vessels in the eye, for example PDT.
[0013] The anti-VEGF aptamer may be administer intraocullary by
injection into the eye. Alternatively, the aptamer may be delivered
using an intraocular implant.
[0014] The methods of the invention can be used to treat a variety
of neovascular diseases, including but not limited to, ischemic
retinopathy, intraocular neovascularization, age-related macular
degeneration, corneal neovascularization, retinal
neovascularization, choroidal neovascularization, diabetic macular
edema, diabetic retina ischemia, diabetic retinal edema, and
proliferative diabetic retinopathy.
[0015] Other advantages and features of the present invention will
be apparent from the following detailed description thereof and
from the claims.
Definitions
[0016] By "ocular neovascular disease" is meant a disease
characterized by ocular neovascularization, i.e. the development of
abnormal blood vessels in the eye of a patient.
[0017] By "patient" is meant any animal having ocular tissue that
may be subject to neovascularization. Preferably, the animal is a
mammal, which includes, but is not limited to, humans and other
primates. The term also includes domesticated animals, such as
cows, hogs, sheep, horses, dogs, and cats.
[0018] By "phototherapy" is meant any process or procedure in which
a patient is exposed to a specific dose of light of a particular
wavelength, including laser light, in order to treat a disease or
other medical condition.
[0019] By "photodynamic therapy" or "PDT" is meant any form of
phototherapy that uses a light-activated drug or compound, referred
to herein as a photosensitizer, to treat a disease or other medical
condition characterized by rapidly growing tissue, including the
formation of abnormal blood vessels (i.e., angiogenesis).
Typically, PDT is a two-step process that involves local or
systemic administration of the photosensitizer to a patient
followed by activation of the photosensitizer by irradiation with a
specific dose of light of a particular wavelength.
[0020] By "anti-VEGF agent" is meant a compound that inhibits the
activity or production of vascular endothelial growth factor
("VEGF").
[0021] By "photosensitizer" or "photoactive agent" is meant a
light-absorbing drug or other compound that upon exposure to light
of a particular wavelength becomes activated thereby promoting a
desired physiological event, e.g., the impairment or destruction of
unwanted cells or tissue.
[0022] By "thermal laser photocoagulation" is meant a form of
photo-therapy in which laser light rays are directed into the eye
of a patient in order to cauterize abnormal blood vessels in the
eye to seal them from further leakage.
[0023] By "effective amount" is meant an amount sufficient to treat
a symptom of an ocular neovascular disease.
[0024] The term "light" as used herein includes all wavelengths of
electromagnetic radiation, including visible light. Preferably, the
radiation wavelength is selected to match the wavelength(s) that
excite(s) the photosensitizer. Even more preferably, the radiation
wavelength matches the excitation wavelength of the photosensitizer
and has low absorption by non-target tissues.
BRIEF DESCRIPTION OF THE DRAWING
[0025] FIG. 1 is the chemical structure of the anti-VEGF agent
NX1838.
DETAILED DESCRIPTION
[0026] VEGF (Vascular Endothelial Growth Factor) is an important
stimulus for the growth of new blood vessels in the eye. We have
discovered that anti-VEGF therapy provides a safe and effective
treatment for neovascular disease, especially when combined with a
secondary therapy that is able to reduce or eliminate ocular
neovascularization, such as, for example, photodynamic therapy
(PDT). We found that the combination of these therapies is far
superior at treating conditions characterized by the development of
unwanted neovasculature in the eye than most conventional
treatments, including the use of either of these therapies
alone.
[0027] Accordingly, the present invention provides a method of
treating an ocular neovascular disease which involves administering
to a patient an anti-VEGF agent and treating the patient with
phototherapy (e.g., PDT) or with other therapies, such as
photocoagulation, that destroy abnormal blood vessels in the eye.
This method can be used to treat a number of ophthamalogical
diseases and disorders marked by the development of ocular
neovascularization, including but not limited to, ischemic
retinopathy, intraocular neovascularization, age-related macular
degeneration, corneal neovascularization, retinal
neovascularization, choroidal neovascularization, diabetic macular
edema, diabetic retina ischemia, diabetic retinal edema, and
proliferative diabetic retinopathy.
[0028] Anti-VEGF Therapy
[0029] A variety of anti-VEGF therapies that inhibit the activity
or production of VEGF, including aptamers and VEGF antibodies, are
available and can be used in the methods of the present invention.
The preferred anti-VEGF agents are nucleic acid ligands of VEGF,
such as those described in U.S. Pat. Nos. 6,168,778 B1; 6,147,204;
6,051,698; 6,011,020; 5,958,691; 5,817,785; 5,811,533; 5,696,249;
5,683,867; 5,670,637; and 5,475,096. A particularly preferred
anti-VEGF agent is EYE001 (previously referred to as NX1838), which
is a modified, pegylated aptamer that binds with high affinity to
the major soluble human VEGF isoform and has the general structure
shown in FIG. 1 (described in U.S. Pat. No. 6,168,788; Journal of
Biological Chemistry, Vol. 273(32): 20556-20567 (1998); and In
Vitro Cell Dev. Biol.-Animal Vol. 35:533-542 (1999)).
[0030] Alternatively, the anti-VEGF agents may be, for example,
VEGF antibodies or antibody fragments, such as those described in
U.S. Pat. Nos. 6,100,071; 5,730,977; and WO 98/45331. Other
suitable anti-VEGF agents or compounds that may be used in
combination with anti-VEGF agents according to the present
invention include, but are not limited to, antibodies specific to
VEGF receptors (e.g., U.S. Pat. Nos. 5,955,311; 5,874,542; and
5,840,301); compounds that inhibit, regulate, and/or modulate
tyrosine kinase signal transduction (e.g., U.S. Pat. No. 6,313,138
B1); VEGF polypepides (e.g., U.S. Pat. No. 6,270,933 B1 and WO
99/47677); oligonucleotides that inhibit VEGF expression at the
nucleic acid level, for example antisense RNAs (e.g., U.S. Pat.
Nos. 5,710,136; 5,661,135; 5,641,756; 5,639,872; and 5,639,736);
retinoids (e.g., U.S. Pat. No. 6,001,885); growth factor-containing
compositions (e.g., U.S. Pat. No. 5,919,459); antibodies that bind
to collagens (e.g., WO 00/40597); and various organic compounds and
other agents with angiogenesis inhibiting activity (U.S. Pat. Nos.
6,297,238 B 1; 6,258,812 B 1; and 6,114,320).
[0031] Administration of Anti-VEGF Agents
[0032] Once a patient has been diagnosed with a neovascular
disorder of the eye, the patient is treated by administration of an
anti-VEGF agent in order to block the negative effects of VEGF,
thereby alleviating the symptoms associated with the
neovascularization. As discussed above, a wide variety of anti-VEGF
agents are known in the art and may be used in the present
invention. Methods for preparing these anti-VEGF agents are also
well-known and many are commercially available medications.
[0033] The anti-VEGF agents can be administered systemically, e.g.
orally or by IM or IV injection, in admixture with a
pharmaceutically acceptable carrier adapted for the route of
administration. A variety of physiologically acceptable carriers
can be used to administer the anti-VEGF agents and their
formulations are known to those skilled in the art and are
described, for example, in Remington's Pharmaceutical Sciences,
(18.sup.th edition), ed. A. Gennaro, 1990, Mack Publishing Company,
Easton, Pa. and Pollock et al.
[0034] The anti-VEGF agents are preferably administered
parenterally (e.g., by intramuscular, intraperitoneal, intravenous,
intraocular, intravitreal, or subcutaneous injection or implant).
Formulations for parenteral administration include sterile aqueous
or non-aqueous solutions, suspensions, or emulsions. A variety of
aqueous carriers can be used, e.g., water, buffered water, saline,
and the like. Examples of other suitable vehicles include
polypropylene glycol, polyethylene glycol, vegetable oils, gelatin,
hydrogenated naphalenes, and injectable organic esters, such as
ethyl oleate. Such formulations may also contain auxiliary
substances, such as preserving, wetting, buffering, emulsifying,
and/or dispersing agents. Biocompatible, biodegradable lactide
polymer, lactide/glycolide copolymer, or polyoxyethylene-polyoxyp-
ropylene copolymers may be used to control the release of the
active ingredients.
[0035] Alternatively, the anti-VEGF agents can be administered by
oral ingestion. Compositions intended for oral use can be prepared
in solid or liquid forms, according to any method known to the art
for the manufacture of pharmaceutical compositions. The
compositions may optionally contain sweetening, flavoring,
coloring, perfuming, and preserving agents in order to provide a
more palatable preparation.
[0036] Solid dosage forms for oral administration include capsules,
tablets, pills, powders, and granules. Generally, these
pharmaceutical preparations contain active ingredient admixed with
non-toxic pharmaceutically acceptable excipients. These may
include, for example, inert diluents, such as calcium carbonate,
sodium carbonate, lactose, sucrose, glucose, mannitol, cellulose,
starch, calcium phosphate, sodium phosphate, kaolin and the like.
Binding agents, buffering agents, and/or lubricating agents (e.g.,
magnesium stearate) may also be used. Tablets and pills can
additionally be prepared with enteric coatings.
[0037] Liquid dosage forms for oral administration include
pharmaceutically acceptable emulsions, solutions, suspensions,
syrups, and soft gelatin capsules. These forms contain inert
diluents commonly used in the art, such as water or an oil medium,
and can also include adjuvants, such as wetting agents, emulsifying
agents, and suspending agents.
[0038] The anti-VEGF agents can also be administered topically, for
example, by patch or by direct application to the eye, or by
iontophoresis.
[0039] The anti-VEGF agents may be provided in sustained release
compositions, such as those described in, for example, U.S. Pat.
Nos. 5,672,659 and 5,595,760. The use of immediate or sustained
release compositions depends on the nature of the condition being
treated. If the condition consists of an acute or over-acute
disorder, treatment with an immediate release form will be
preferred over a prolonged release composition. Alternatively, for
certain preventative or long-term treatments, a sustained released
composition may be appropriate.
[0040] The anti-VEGF agent may also be delivered using an
intraocular implant. Such implants may be biodegradable and/or
biocompatible implants, or may be non-biodegradable implants. The
implants may be permeable or impermeable to the active agent, and
may be inserted into a chamber of the eye, such as the anterior or
posterior chambers or may be implanted in the schelra,
transchoroidal space, or an avascularized region exterior to the
vitreous. In a preferred embodiment, the implant may be positioned
over an avascular region, such as on the sclera, so as to allow for
transcleral diffusion of the drug to the desired site of treatment,
e.g. the intraocular space and macula of the eye. Furthermore, the
site of transcleral diffusion is preferably in proximity to the
macula.
[0041] Examples of implants for delivery of an anti-VEGF agent
include, but are not limited to, the devices described in U.S. Pat.
Nos. 3,416,530; 3,828,777; 4,014,335; 4,300,557; 4,327,725;
4,853,224; 4,946,450; 4,997,652; 5,147,647; 5,164,188; 5,178,635;
5,300,114; 5,322,691; 5,403,901; 5,443,505; 5,466,466; 5,476,511;
5,516,522; 5,632,984; 5,679,666; 5,710,165; 5,725,493; 5,743,274;
5,766,242; 5,766,619; 5,770,592; 5773,019; 5,824,072; 5,824,073;
5,830,173; 5,836,935; 5,869,079, 5,902,598; 5,904,144; 5,916,584;
6,001,386; 6,074,661; 6,110,485; 6,126,687; 6,146,366; 6,251,090;
and 6,299,895, and in WO 01/30323 and WO 01/28474, all of which are
incorporated herein by reference.
[0042] Dosage
[0043] The amount of active ingredient that is combined with the
carrier materials to produce a single dosage will vary depending
upon the subject being treated and the particular mode of
administration. Generally, the anti-VEGF agent should be
administered in an amount sufficient to reduce or eliminate a
symptom of an ocular neovascular disease.
[0044] Dosage levels on the order of about 1 .mu.g/kg to 100 mg/kg
of body weight per administration are useful in the treatment of
the above mentioned neovascular disorders. When administered
directly to the eye, the preferred dosage range is about 0.3 mg to
about 3 mg per eye. The dosage may be administered as a single dose
or divided into multiple doses. In general, the desired dosage
should be administered at set intervals for a prolonged period,
usually at least over several weeks, although longer periods of
administration of several months or more may be needed.
[0045] One skilled in the art will appreciate that the exact
individual dosages may be adjusted somewhat depending on a variety
of factors, including the specific anti-VEGF agent being
administered, the time of administration, the route of
administration, the nature of the formulation, the rate of
excretion, the particular disorder being treated, the severity of
the disorder, and the age, weight, health, and gender of the
patient. Wide variations in the needed dosage are to be expected in
view of the differing efficiencies of the various routes of
administration. For instance, oral administration generally would
be expected to require higher dosage levels than administration by
intravenous or intravitreal injection. Variations in these dosage
levels can be adjusted using standard empirical routines for
optimization, which are well-known in the art. The precise
therapeutically effective dosage levels and patterns are preferably
determined by the attending physician in consideration of the above
identified factors.
[0046] In addition to treating pre-existing neovascular diseases,
anti-VEGF agents can be administered prophylactically in order to
prevent or slow the onset of these disorders. In prophylactic
applications, an anti-VEGF agent is administered to a patient
susceptible to or otherwise at risk of a particular neovascular
disorder. Again, the precise amounts that are administered depend
on various factors such as the patient's state of health, weight,
etc.
[0047] Effectiveness of Anti-VEGF Therapy
[0048] In order to assess the effectiveness of anti-VEGF therapy to
treat ocular neovascularization, we conducted a number of studies,
which are described in the examples below, that involved the
administration of an anti-VEGF aptamer with and without
photodynamic therapy in patients suffering from subfoveal choroidal
neovascularization secondary to age-related macular degeneration. A
Phase 1A single intravitreal injection study of anti-VEGF therapy
for patients with subfoveal choroidal neovascularization (CNV)
secondary to age-related macular degeneration (AMD) revealed an
excellent safety profile (Example 6).
[0049] Ophthalmic evaluation revealed that 80% of patients showed
stable or improved 10 vision 3 months after treatment and that 27%
of eyes demonstrated a 3-line or greater improvement in vision on
the ETDRS chart at this time period. No significant related adverse
events were reported locally or systemically. These data
demonstrated that anti-VEGF therapy is a promising new avenue for
the treatment of neovascular diseases of the eye, including
exudative macular degeneration and diabetic retinopathy.
[0050] We also performed a Phase 1B multiple descending dose safety
study of anti-VEGF therapy using multiple intravitreal injections
of the anti-VEGF aptamer with or without photodynamic therapy in
patients with subfoveal CNV secondary to AMD (Example 7). The
safety study showed no significant safety issues related to the
drug. Ophthalmic evaluation revealed that 87.5% of patients that
received the anti-VEGF aptamer alone showed stable or improved
vision 3 months after treatment and that 25% of eyes demonstrated a
3-line or greater improvement in vision on the ETDRS chart at this
time period. A 60% 3-line gain at 3 months was noted in patients
that received both the anti-VEGF aptamer and photodynamic therapy.
Multiple intravitreal injections of the anti-VEGF aptamer were very
well tolerated in this Phase 1B study.
[0051] The results of this Phase 1B multiple intravitreal injection
clinical study of anti-VEGF therapy (Example 7) expand the
excellent safety profile reported by our Phase 1A single-injection
study (Example 6). Specifically, the Phase 1B study shows the
intraocular and systemic safety of three consecutive anti-VEGF
aptamer intravitreal injections given monthly. No serious related
adverse events were noted. The adverse events encountered appeared
to be unrelated or minor events in some cases probably due to the
intravitreal injection itself.
[0052] The 3-line gain observed in 25% of the aptamer only treated
group at 3 months compares favorably to historical controls such as
the results of the pivotal trial of PDT (2.2%) and its controls
(1.4%) at 3 months (Arch Ophthalmol 1999, 117:1329-1345) and a sham
radiation control group (3%) (Ophthalmology 1999, 106;12:2239-2247)
where no more than 3% of patients showed such an improvement at
this same time period.
[0053] The 25% 3-line gain at 3 months is consistent with the 26.7%
improvement rate noted in the Phase 1A study of the aptamer. It may
be that the anti-permeability effects of the drug caused resorption
of subretinal fluid and, thus improved vision in these cases.
Interestingly, a recent study using an anti-VEGF antibody fragment
from Genentech also showed a 26% 3-line gain rate in a Phase 1
clinical trial. This antibody fragment shares the same mechanism of
blocking extracellular VEGF as the anti-VEGF aptamer.
[0054] The stabilization or improvement rate of 87.5% observed at 3
months in the Phase IB study also compares favorably with the 50.5%
rate for the PDT-treated patients in that pivotal trial (Arch
Ophthalmol 1999, 117:1329-1345), the 44% rate in the PDT controls,
and 48% rate in the sham radiation control group (Ophthalmology
1999, 106;12:2239-2247).
[0055] The 60% 3-line gain at 3 months in the patients that
received both the anti-VEGF aptamer and PDT was also very
encouraging. In the pivotal Phase 3 PDT trial only 2.2% of patients
showed such visual improvement (Arch Ophthalmol 1999,
117:1329-1345). Both of these study groups included eyes with
classic subfoveal CNV. The improvement in vision observed in these
eyes is supported by the finding that the investigators choose to
re-treat with PDT at 3 months in only 40% of cases compared to the
93% re-treatment rate reported in the pivotal PDT trial (Arch
Ophthalmol 1999, 117:1329-1345).
[0056] In addition, numerous pre-clinical studies now show that
anti-VEGF therapy can prevent VEGF-induced neovascularization of
the cornea, iris, retina, and choroid (Arch Ophthalmol 1996,
114:66-7; Invest Ophthalmol Vis Sci 1994, 35:101). The pre-clinical
studies described below in Examples 1-5 with EYE001 provide
evidence that anti-VEGF therapy may be useful in decreasing
vascular permeability and ocular neovascularization. The anti-VEGF
aptamer showed great efficacy in the ROP retinal neovascularization
model where 80% of retinal neovascularization was inhibited
compared to controls (p=0.0001). The Miles assay model showed
almost complete attenuation of VEGF mediated vascular leakage
following addition of EYE001 and the corneal angiogenesis model
also showed a significant reduction in neovascularization with
EYE001. The Miles Assay study in guinea pigs suggests that the
anti-VEGF aptamer can significantly decrease vascular permeability.
This property of decreasing vascular permeability may prove to be
clinically important for decreasing fluid and edema in CNV and
diabetic macular edema. Thus, anti-VEGF therapy may act both as an
anti-permeability and/or anti-angiogenic agent.
[0057] Photodynamic Therapy (PDT)
[0058] As discussed above, one embodiment of the method of the
invention involves administering an anti-VEGF agent in combination
with photodynamic therapy (PDT). PDT is a two-step process that
starts with the local or systemic administration of a
light-absorbing photosensitive agent, such as a porphyrin
derivative, that accumulates selectively in target tissues of the
patient. Upon irradiation with light of an activating wavelength,
reactive oxygen species are produced in cells containing the
photosensitizer, which promote cell death. For example, in the
treatment of eye diseases characterized by ocular
neovascularization, a photosensitizer is selected that accumulates
in the neovasculature of the eye. The patient's eye is then exposed
to light of an appropriate wavelength, which results in the
destruction of the abnormal blood vessels, thereby improving the
patient's visual acuity.
[0059] Photosensitizers
[0060] The photodynamic therapy according to the invention can be
performed using any of a number of photoactive compounds. For
example, the photosensitizer can be any chemical compound that
collects in one or more types of selected target tissues and, when
exposed to light of a particular wavelength, absorbs the light and
induces impairment or destruction of the target tissues. Virtually
any chemical compound that homes to a selected target and absorbs
light may be used in this invention. Preferably, the
photosensitizer is nontoxic to the animal to which it is
administered and is capable of being formulated in a nontoxic
composition. The photosensitizer is also preferably nontoxic in its
photodegraded form. Ideal photosensitizers are characterized by a
lack of toxicity to cells in the absence of the photochemical
effect and are readily cleared from non-target tissues.
[0061] A comprehensive listing of photosensitizers may be found,
for example, in Kreimer-Birnbaum, Sem. Hematol. 26:157-73, 1989.
Photosensitive compounds include, but are not limited to, chlorins,
bacteriochlorins, phthalocyanines, porphyrins, purpurins,
merocyanines, pheophorbides, psoralens, aminolevulinic acid (ALA),
hematoporphyrin derivatives, porphycenes, porphacyanine, expanded
porphyrin-like compounds and pro-drugs such as 6-aminolevulinic
acid, which can produce drugs such as protoporphyrin. (See, e.g.,
photosenitizers described in any of U.S. Pat. Nos. 5,438,071;
5,405,957; 5,198,460; 5,190,966; 5,173,504; 5,171,741; 5,166,197;
5,095,030; 5,093,349; 5,079,262; 5,028,621; 5,002,962; 4,968,715;
4,920,143; 4,883,790; 4,866,168; and 4,649,151.) Preferred
photosensitizing agents are benzoporphyrin derivatives (BPD),
monoaspartyl chlorin e6, zinc phthalocyanine, tin etiopurpurin,
tetrahydroxy tetraphenylporphyrin, and porfimer sodium
(PHOTOFRIN.RTM.). A particularly potent group of photosensitizers
includes green porphyrins, which are described in detail in Levy et
al., U.S. Pat. No. 5,171,749.
[0062] Any of the photosensitizers described above can be used in
the methods of the invention. Of course, mixtures of two or more
photoactive compounds can also be used; however, the effectiveness
of the treatment depends on the absorption of light by the
photosensitizer so that if mixtures are used, components with
similar absorption maxima are preferred.
[0063] The photosensitizing agents of the present invention
preferably have an absorption spectrum that is within the range of
wavelengths between 350 nm and 1200 nm, preferably between about
400 and 900 nm and, most preferably, between 600 and 800 nm.
[0064] The photosensitizer is formulated so as to provide an
effective concentration to the target ocular tissue. The
photosensitizer may be coupled to a specific binding ligand which
may bind to a specific surface component of the target ocular
tissue or, if desired, by formulation with a carrier that delivers
higher concentrations to the target tissue. The nature of the
formulation will depend in part on the mode of administration and
on the nature of the photosensitizer selected. Any pharmaceutically
acceptable excipient, or combination thereof, appropriate to the
particular photoactive compound may be used. Thus, the
photosensitizer may be administered as an aqueous composition, as a
transmucosal or transdermal composition, or in an oral
formulation.
[0065] As previously mentioned, the method of the invention is
particularly effective to treat patients suffering from loss of
visual acuity associated with unwanted neovasculature. Increased
numbers of LDL receptors have been shown to be associated with
neovascularization. Green porphyrins, and in particular BPD-MA,
strongly interact with such lipoproteins. LDL itself can be used as
a carrier for green porphyrins, or liposomal formulations may be
used. Liposomal formulations are believed to deliver green
porphyrins selectively to the low-density lipoprotein component of
plasma which, in turn acts as a carrier to deliver the active
ingredient more effectively to the desired site. By increasing the
partitioning of the green porphyrin into the lipoprotein phase of
the blood, liposomal formulations can result in a more efficient
delivery of the photosensitizer to neovasculature. Compositions of
green porphyrins involving lipocomplexes, including liposomes, are
described in U.S. Pat. No. 5,214,036. Liposomal BPD-MA for
intravenous administration can be obtained from QLT
PhotoTherapeutics Inc., Vancouver, British Columbia.
[0066] The photosensitizer can be administered locally or
systemically in any of a wide variety of ways, for example, orally,
parenterally (e.g., intravenous, intramuscular, intraperitoneal or
subcutaneous injection), topically via patches or implants, or the
compound may be placed directly in the eye. The photosensitizing
agent can be administered in a dry formulation, such as pills,
capsules, suppositories, or patches. The photosensitizing agent
also may be administered in a liquid formulation, either alone with
water, or with pharmaceutically acceptable excipients, such as are
disclosed in Remington's Pharmaceutical Sciences, supra. The liquid
formulation also can be a suspension or an emulsion. Suitable
excipients for suspensions for emulsions include water, saline,
dextrose, glycerol, and the like. These compositions may contain
minor amounts of nontoxic auxiliary substances such as wetting or
emulsifying agents, antioxidants, pH buffering agents, and the
like.
[0067] The dose of photosensitizer can vary widely depending a
variety of factors, such as the type of photosensitizer; the mode
of administration; the formulation in which it is carried, such as
in the form of liposomes; or whether it is coupled to a
target-specific ligand, such as an antibody or an immunologically
active fragment. Other factors which impact the dose of
photosensitizing agent include the target cell(s) sought, the
patient's weight, and the timing of the light treatment. While
various photoactive compounds require different dosage ranges, if
green porphyrins are used, a typical dosage is of the range of
0.1-50 mg/M.sup.2 (of body surface area) preferably from about 1-10
mg/M.sup.2 and even more preferably about 2-8 mg/M.sup.2.
[0068] The various parameters used for photodynamic therapy in the
invention are interrelated. Therefore, the dose should also be
adjusted with respect to other parameters, for example, fluence,
irradiance, duration of the light used in photodynamic therapy, and
time interval between administration of the dose and the
therapeutic irradiation. All of these parameters should be adjusted
to produce significant enhancement of visual acuity without
significant damage to the eye tissue.
[0069] Light Treatment
[0070] After the photosensitizer has been administered to the
patient, the target ocular tissue is irradiated with light at a
wavelength that is absorbed by the photosensitizer that was used.
The spectra for the photosensitizers described herein are known in
the art; for any particular photoactive compound, it is a trivial
matter to ascertain the spectrum. For green porphyrins, the desired
wavelength range is generally between about 550 and 695 nm. A
wavelength in this range is especially preferred for enhanced
penetration into bodily tissues.
[0071] As a result of being exposed to light, the photosensitizer
enters an excited state and is believed to interact with other
compounds to form reactive intermediates, such as singlet oxygen,
which can cause disruption of cellular structures. Possible
cellular targets include the cell membrane, mitochondria, lysosomal
membranes, and the nucleus. Evidence from tumor and neovascular
models indicates that occlusion of the vasculature is a major
mechanism of photodynamic therapy, which occurs by damage to
endothelial cells, with subsequent platelet adhesion,
degranulation, and thrombus formation.
[0072] The fluence during the irradiating treatment can vary
widely, depending on type of tissue, depth of target tissue, and
the amount of overlying fluid or blood, but preferably varies from
about 50-200 Joules/cm.sup.2.
[0073] The irradiance typically varies from about 150-900
mW/cm.sup.2, with the range between about 150-600 mW/cm.sup.2 being
preferred. However, the use of higher irradiances may be selected
as effective and having the advantage of shortening treatment
times.
[0074] The optimum time following photoactive agent administration
until light treatment can also vary widely depending on the mode of
administration, the form of administration, and the specific ocular
tissue being targeted. Typical times after administration of the
photoactive agent range from about 1 minute to about 2 hours,
preferably about 5-30 minutes, and more preferably about 10-25
minutes.
[0075] The duration of radiation exposure is preferably between
about 1 and 30 minutes, depending on the power of the radiation
source. The duration of light irradiation also depends on the
fluence desired. For example, for an irradiance of 600 mW/cm.sup.2,
a fluence of 50 J/cm.sup.2 requires 90 seconds of irradiation; 150
J/cm.sup.2 requires 270 seconds of irradiation.
[0076] The radiation is further defined by its intensity, duration,
and timing with respect to dosing with the photosensitive agent
(post injection interval). The intensity must be sufficient for the
radiation to penetrate skin and/or to reach the target tissues to
be treated. The duration must be sufficient to photoactivate enough
photosensitive agent to act on the target tissues. Both intensity
and duration must be limited to avoid overtreating the patient. The
post injection interval before light application is important,
because in general the sooner light is applied after the
photosensitive agent is administered, 1) the lower is the required
amount of light and 2) the lower is the effective amount of
photosensitive agent.
[0077] Clinical examination and fundus photography typically reveal
no color change immediately following photodynamic therapy,
although a mild retinal whitening occurs in some cases after about
24 hours. Closure of choroidal neovascularization is preferably
confirmed histologically by the observation of damage to
endothelial cells. Observations to detect vacuolated cytoplasm and
abnormal nuclei associated with disruption of neovascular tissue
may also be evaluated.
[0078] In general, effects of the photodynamic therapy as regards
reduction of neovascularization can be performed using standard
fluorescein angiographic techniques at specified periods after
treatment. The effectiveness of PDT may also be determined through
a clinical evaluation of visual acuity, using means standard in the
art, such as conventional eye charts in which visual acuity is
evaluated by the ability to discern letters of a certain size,
usually with five letters on a line of given size.
[0079] Other Therapies for Treating Neovascular Disease
[0080] In addition to PDT, there are a number of other therapies
for treating neovascular disease which may be used in combination
with anti-VEGF therapies. For example, a form of photo-therapy
known as Thermal Laser Photocoagulation is a standard ophthalmic
procedure for the treatment of a range of eye disorders, including
retinal vascular problems (e.g. diabetic retinopathy), choroidal
vascular problems and macular lesions (e.g. senile macular
degeneration). This procedure involves the use of laser light to
cauterize abnormal blood vessels in the eye of a patient in order
to seal them from further leakage. (See, e.g. Arch. Ophthalmol.
1991, 109:1109-1114). Alternatively, compounds capable of
diminishing or preventing the development of unwanted
neovasculature, including other anti-VEGF agents, anti-angiogenesis
agents, or other agents that inhibit the development of ocular
neovascularization may be used in combination with anti-VEGF
therapy.
[0081] The features and other details of the invention will now be
more particularly described and pointed out in the following
examples describing preferred techniques and experimental results.
These examples are provided for the purpose of illustrating the
invention and should not be construed as limiting.
EXAMPLES
[0082] In the following Examples, the anti-VEGF pegylated aptamer
EYE001 was used. As discussed above, this aptamer is a polyethylene
glycol (PEG)-conjugated oligonucleotide that binds to the major
soluble human VEGF isoform, VEGF.sub.165, with high specificity and
affinity. The aptamer binds and inactivates VEGF in a manner
similar to that of a high-affinity antibody directed towards VEGF.
Examples 1-5 report the pre-clinical results of studies with the
anti-VEGF aptamer in various models of ocular neovascularization,
Example 6 reports the clinical phase IA safety results in humans
with exudative AMD, and Example 7 reports the clinical phase IB
results. Generally, dosages and concentrations are expressed as the
oligonucleotide weight of EYE001 (NX1838) only and are based on an
approximate extinction coefficient for the aptamer of 31
.mu.g/mL/A.sub.260 unit.
Example 1
Cutaneous Vascular Permeability Assay (Miles Assay)
[0083] One of the biological activities of VEGF is to increase
vascular permeability through specific binding to receptors on
vascular endothelial cells. The interaction results in relaxation
of the tight endothelial junctions with subsequent leakage of
vascular fluid. Vascular leakage induced by VEGF can be measured
in-vivo by following the leakage of Evans Blue Dye from the
vasculature of the guinea pig as a consequence of an intradermal
injection of VEGF (Dvorak H F, Brown L F, Detmar M, Dvorak A M.
Vascular Permeability Factor/Vascular Endothelial Growth Factor,
Microvascular Hyperpermeability, and Angiogenesis. Am J Pathol.
1995, 146:1029.) Similarly, the assay can be used to measure the
ability of a compound to block this biological activity of
VEGF.
[0084] VEGF.sub.165 (20-30 nM) was premixed ex-vivo with EYE001 (30
nM to 1 .mu.M) and subsequently administered by intradermal
injection into the shaved skin on the dorsum of guinea pigs. Thirty
minutes following injection, the Evans Blue dye leakage around the
injection sites was quantified by use of a computerized
morphometric analysis system. The data (not shown) demonstrated
that VEGF-induced leakage of the indicator dye from the vasculature
can be almost completely inhibited by the co-administration of
EYEOO 1 at concentrations as low as 100 nM.
Example 2
Corneal Angiogenesis Assay
[0085] Methacyrate polymer pellets containing VEGF.sub.165 (3 pmol)
were implanted into the corneal stroma of rats to induce blood
vessel growth into the normally avascular cornea. EYE001 was
administered intravenously to the rats at doses of 1,3, and 10
mg/kg either once or twice daily for 5 days. At the end of the
treatment period, all of the individual corneas were
photomicrographed. The extent to which new blood vessels developed
in the corneal tissue, and their inhibition by EYE001, were
quantified by standardized morphometric analysis of the
photomicrographs.
[0086] The data (not shown) demonstrated that systemic treatment
with EYE001 results in significant inhibition (65%) of
VEGF-dependent angiogenesis in the cornea when compared to
treatment with phosphate buffered saline (PBS). Once daily
treatment with 10 mg/kg was as effective as twice daily treatment.
The 3 mg/kg dose had activity similar to the 10 mg/kg dose but
significant efficacy was not evident at 1 mg/kg.
Example 3
Retinopathy of Prematurity Study
[0087] Even though ROP is clearly distinct from diabetic
retinopathy and AMD, the mouse model of ROP has been used to
demonstrate a role for VEGF in the abnormal retinal vascularization
that occurs in this disease (Smith L E, Wesolowski E, McLellan A,
Kostyk S K, Amato D R, Sullivan R, D'Amore P A. Oxygen-induced
retinopathy in the mouse. Invest Ophthalmol Vis Sci. 1994, 35:101.)
These data provided a rationale for studying the anti-angiogenic
properties of EYE001 in this model.
[0088] Litters of 9, 8, 8, 7 and 7 mice, respectively, were left in
room air or made hyperoxic and were treated intraperitoneally with
PBS or EYE001 (1, 3, or 10 mg/kg/day). The endpoint of the assay,
outgrowth of new capillaries through the inner limiting membrane of
the retina into the vitreous humor, was assessed by microscopic
identification and counting of the neovascular buds in 20
histologic sections of each eye from all of the treated and control
mice. A reduction in retinal neovasculature of 80% relative to the
untreated control was seen at both the 10 mg/kg and 3 mg/kg doses
(p=0.0001 for both).
Example 4
Human Tumor Xenografts
[0089] The in-vivo efficacy of EYE001 was tested in human tumor
xenografts (A673 rhabdomyosarcoma and Wilms tumor) implanted in
nude mice. In both cases, mice were treated with 10 mg/kg EYE001
given intraperitoneally once a day following development of
established tumors (200 mg). Control groups were treated with a
sequence scrambled control aptamer (oligonucleotide).
[0090] Treatment of mice with 10 mg/kg of EYE001 once daily
inhibited A673 rhabdomyosarcoma tumor growth by 80% and Wilms tumor
by 84% relative to the control. In the Wilms tumor model, two weeks
after termination of therapy, tumor size rebounded so vigorously in
treated animals that there was no longer any difference in tumor
size compared to controls.
Example 5
Intravitreal Pharmacokinetics of EYE001 in Rabbits
[0091] Rabbits were obtained and cared for in accordance with all
applicable state and federal guidelines and adhered to the
"Principles of Laboratory Animal Care" (NIH publication #85-23,
revised 1985). A total of 18 male New Zealand White rabbits were
administered EYE001 by intravitreous injection. Each animal
received a dose as a bilateral injection of 0.50 mg/eye (1.0
mg/animal) in a volume of 40 .mu.L/eye. EDTA-Plasma and vitreous
humor samples were collected over a 28-day period following dose
administration and stored frozen (-70.degree. C.) until assayed.
Vitreous humor from each eye was collected separately after the
animals were sacrificed by exsanguination. EYE001 concentrations in
vitreous humor samples were determined by an HPLC assay method
similar to that described previously by Tucker et al. (Detection
and plasma pharmacokinetics of an anti-vascular endothelial growth
factor oligonucleotide-aptamer (NX1838) in rhesus monkeys. J.
Chromatogr. Biomed. Appl. 1999, 732:203-212) and by a dual
hybridization assay method similar to that described previously by
Drolet et al. (Pharmacokinetics and Safety of an Anti-Vascular
Endothelial Growth Factor Aptamer (NX1838) Following Injection into
the Vitreous Humor of Rhesus Monkeys. Pharm. Res., 2000,
17:1503-1510.) The vitreous humor concentration was calculated by
averaging the results from both assays. EYE001 concentrations in
plasma were determined only by the dual hybridization assay.
[0092] Following a single dose of EYE001 as a bilateral
administration of 0.50 mg/eye (1.0 mg/animal), the initial vitreous
humor levels were approximately 350 .mu.g/mL and decreased by an
apparent first order elimination process to approximately 1.7
.mu.g/mL by day 28. The estimated terminal half-life was 83 hours
similar to the 94-hour half-life observed in rhesus monkeys (Drolet
et al., supra). At four weeks following administration of EYEOO 1,
drug levels in the vitreous humor (190 nM) remained well above the
KD for VEGF (200 pM) suggesting that once monthly dosing in humans
is appropriate, assuming that pharmacokinetic parameters are
comparable in the rabbit and human vitreous humor. In contrast to
the high levels of EYE001 found in the vitreous humor, the plasma
concentrations were significantly lower and ranged from 0.092 to
0.005 .mu.g/mL from day 1 to day 21. Plasma levels declined by an
apparent first order elimination process as well with an estimated
terminal half-life of 84 hours. The plasma terminal half-life thus
mimicked the vitreous humor half-life as observed in rhesus monkeys
(Drolet et al., supra) and is indicative of classical flip-flop
kinetics in which the clearance from the eye is the
rate-determining step for plasma clearance. These data are
consistent with a highly stable (nuclease resistant) aptamer that
undergoes a slow rate of release from the vitreous humor into the
systemic circulation.
Example 6
Clinical Trial-Phase IA Study
[0093] We performed a multi-centered, open-label, dose-escalation
study of a single intravitreous injection of EYE001 in patients
with subfoveal CNV secondary to age-related macular degeneration
and with a visual acuity worse than 20/200 on the ETDRS chart. The
starting dose was 0.25 mg injected once intravitreously. Dosages of
0.5, 1, 2 and 3 mg were also tested. Complete ophthalmic
examination with fundus photography and fluorescein angiography was
performed. A total of 15 patients were treated.
[0094] Selection Criteria.
[0095] Patients for the study were selected using the following
inclusion and exclusion criteria:
[0096] Inclusion Criteria: Patients were required to be>50 years
and in generally good health, have a best corrected visual acuity
in the study eye worse than 20/200 on the ETDRS chart, and 20/400
or worse for at least the first patient of each cohort (n=3); best
corrected visual acuity in the fellow eye equal to or better than
20/64; subfoveal CNV (classic and/or occult CNV) of >3.5 Macular
Photocoagulation Study (MPS) disc areas in size; clear ocular media
and adequate pupillary dilatation to permit good quality
stereoscopic fundus photography; and intraocular pressure of 22
mmHg or less.
[0097] Exclusion Criteria: Exclusions included significant media
opacities, including cataract, which might interfere with visual
acuity, assessment of toxicity, or fundus photography; presence of
ocular disease, including glaucoma, diabetic retinopathy, retinal
vascular occlusion or other conditions (other than CNV from AMD)
which might significantly affect vision; presence of other causes
of CNV, including pathologic myopia (spherical equivalent of -8
diopters or more negative), the ocular histoplasmosis syndrome,
angioid streaks, choroidal rupture and multifocal choroiditis;
patients in whom additional laser treatment for CNV might be
indicated or considered; any intraocular surgery within 3 months of
study entry; blood occupying >50% of the lesion; previous
vitrectomy; previous or concomitant therapy with another
investigational agent to treat AMD except multivitamins and trace
minerals; any of the following underlying systemic diseases
including uncontrolled diabetes mellitus or presence of diabetic
retinopathy; cardiac disease including myocardial infarction within
12 months prior to study entry, and/or coronary disease associated
with clinical symptoms, and/or indications of ischemia noted on
ECG; stroke (within 12 months of study entry); active bleeding
disorders; any major surgical procedure within one month of study
entry; active peptic ulcer disease with bleeding within 6 months of
study entry; and concomitant systemic therapy with corticosteroids
(e.g. oral prednisone), or other anti-angiogenic drugs (e.g.
thalidomide).
[0098] Study Medication. The drug product was a ready-to-use
sterile solution composed of EYE001 (formerly NX1838) dissolved in
10 mM sodium phosphate and 0.9% sodium chloride buffer injection
and presented in a sterile and pyrogen free 1 cc glass body syringe
barrel, with a coated stopper attached to a plastic plunger, and a
rubber end cap on the pre-attached 27 gauge needle. The pegylated
aptamer was supplied at active drug concentrations of 1, 2.5, 5,
10, 20 or 30 mg/ml of EYE001 (expressed as oligonucleotide content)
in order to provide a 100 .mu.l delivery volume.
[0099] Patient Enrollment.
[0100] Before recruitment of patients into the study, written
Institutional Review Board (IRB) approval of the protocol, informed
consent and any additional patient information was obtained.
[0101] Results.
[0102] A single dose-ranging safety study was performed in 15
patients at doses varying from 0.25 to 3.0 mg/eye without reaching
dose-limiting toxicity. Viscosity of the formulation prevented
further dose escalation past 3 mg. Patients ranged in age from 64
to 92 years old. Eight males and seven females were entered and all
were Caucasian. Eleven of the fifteen patients experienced a total
of seventeen mild or moderate, adverse events including six, which
were probably or possibly related to administration of EYE001: mild
intraocular inflammation, scotoma, visual distortion, hives, eye
pain and fatigue. In addition, there was one severe adverse event,
which was unrelated to test drug. This was the diagnosis of breast
carcinoma in one patient, where the lump had been noted prior to
treatment.
[0103] At 3 months after injection of EYE001, 12 out of 15 (80%)
eyes showed stable or improved vision. Four patients (26.7%) had
significantly improved vision at the same time point, which was
defined as a 3-line, or greater, increase in vision on the ETDRS
chart. Patients with such improved vision at 3 months noted
increases of +6, +4 and +3 lines on an ETDRS chart. No unexpected
visual safety events were noted. Evaluation of color photographs
and fluorescein angiograms revealed no signs of retinal or
choroidal toxicity.
[0104] Our Phase IA clinical study showed that single intravitreal
doses of the anti-VEGF aptamer could be administered safely up to 3
mg/eye. No significant ocular or systemic side effects were
noted.
[0105] Clinicians agree that a minimum of one-year follow-up is
desirable to evaluate any potential treatment for exudative AMD.
Nevertheless, 3-month data is available from some prospective
studies and is useful to assess both ophthalmic safety and any
potential trends of a new therapy.
[0106] Historical controls indicate that only 1.4% (pivotal
photodynamic trial) (Arch Ophthalmol 1999, 117:1329-1345) and 3.0%
(radiation study) (1999, 106; 12:2239-2247) of eyes have shown
significant visual improvement as defined by a gain of 3 or more
lines on an ETDRS chart at 3 months. In addition, the PDT--treated
group of the TAP study (Arch Ophthalmol 1999, 117:1329-1345) only
noted such improved vision in 2.2% of cases at 3 months. These
findings confirm our clinical impression that it is rare to see
significant visual improvement at any time frame with any type
(classic, occult or mixed) of CNV secondary to AMD.
[0107] In our study, at three months after intravitreal
administration of the anti-VEGF aptamer, 80% of eyes showed
stabilized or improved vision with 26.7% showing an increase in 3
or more lines on the ETDRS chart. These visual improvements are
supported by clinical and angiographic findings in some of the
aptamer-treated patients. Stabilization of vision has always been
the goal of exudative AMD studies, so the significant visual acuity
improvement (3 ETDRS lines) seen in 26.7% of patients at 3 months
with only one dose was unexpected. Clearly, historical controls are
inappropriate for comparison. In addition, the short follow-up
period, small sample size, and different CNV type (i.e. percentage
of classic, occult, or mixed CNV) precluded any final conclusions
or comparisons. However, it appears that the aptamer-treated eyes
have certainly shown at least excellent visual safety at 3 months
and justify further studies.
[0108] In summary, pre-clinical and early clinical results with
single intravitreal injections of the anti-VEGF aptamer are very
encouraging. The safety of single-dose intravitreal injections of
dosages up to 3 mg/eye has been established.
Example 7
Clinical Trial-Phase IB Study
[0109] We conducted a multi-center, open-label, repeat dose Phase
IB study of 3 mg/eye of EYE001 (anti-VEGF aptamer) in patients with
subfoveal CNV secondary to AMD with a visual acuity worse than
20/100 in the study eye and better or equal to 20/400 in the fellow
eye. If 3 or more patients experienced Dose-Limiting Toxicity
(DLT's), the dose was reduced to 2 mg and then 1 mg, if necessary.
The intended number of patients to be treated was 20; 10 patients
with the anti-VEGF aptamer alone and 10 patients with both
anti-VEGF therapy and PDT. Eleven sites in the U.S. were selected
for the studies.
[0110] Definition of DLT(s)
[0111] If a patient in the study experienced any of the following
DLTs, the dosage was reduced as described above:
[0112] Ophthalmic DLT:
[0113] Photographic Evaluation.
[0114] Accelerated formation of cataract: progression of one unit
defined by the Age-Related Eye Disease Study (AREDS) Lens Opacity
Grading Protocol as adapted from the Wisconsin Cataract Grading
System.
[0115] Clinical Examination.
[0116] Clinically significant inflammation, which was severe
(obscuring visualization of the retinal vasculature) and vision
threatening.
[0117] Other ocular abnormalities not usually seen in patients with
AMD, such as retinal, arterial, or venous occlusion, acute retinal
detachment, and diffuse retinal hemorrhage.
[0118] Visual acuity: doubling or worsening of the visual angle
(loss of .gtoreq.15 letters); transition to no light perception
(NLP) for patients whose beginning visual acuity score is less than
15 letters unless the loss of vision is due to a vitreous
hemorrhage related to the injection procedure between Days 2
through 7, Days 30-35, or Days 58-63.
[0119] Tonometry: increase from baseline of intraocular pressure
(IOP) by .gtoreq.25 mmHg on two separate examinations at least one
day apart or a sustained pressure of 30 mmHg for more than a week
despite pharmacological intervention.
[0120] Fluorescein Angiogram
[0121] Significant retinal or choroidal vascular abnormalities not
seen at baseline, such as: choroidal nonperfusion (effecting one or
more quadrants) delay in arterio-venous transit times (greater than
15 seconds); retinal arterial or venous occlusion (any deviation
from baseline); or diffuse retinal permeability alteration
effecting retinal circulation in the absence of intraocular
inflammation
[0122] Systemic DLT:
[0123] Grade III (severe) or IV (life-threatening) toxicities, or
any significant severe toxicity deemed related to study drug by the
investigator.
[0124] Selection Criteria.
[0125] Patients for the study were selected using the following
inclusion and exclusion criteria:
[0126] Inclusion Criteria: The ophthalmic criteria included best
corrected visual acuity in the study eye worse than 20/100 on the
ETDRS chart, best corrected visual acuity in the fellow eye equal
to or better than 20/400, subfoveal choroidal neovascularization
with active CNV (either classic and/or occult) of less than 12
total disc areas in size secondary to age related macular
degeneration, clear ocular media and adequate pupillary dilatation
to permit good quality stereoscopic fundus photography, and
intraocular pressure of 2 lmmHg or less. General criteria included
patients of either sex, aged .gtoreq.50 years; performance Status
.ltoreq.2 according to the Eastern Cooperative Oncology Group
(ECOG)/World Health Organization (WHO) scale, normal
electrocardiogram (ECG) or clinically non-significant changes;
women must be using an effective contraceptive, be post-menopausal
for at least 12 months prior to study entry, or surgically sterile;
if not, a serum pregnancy test must be performed within 48 hours
prior to treatment and the result made available prior to treatment
initiation, an effective form of contraceptive should be
implemented for at least 28 days following the last dose of EYE001;
adequate hematological function: hemoglobin .gtoreq.10 g/dl;
platelet count .gtoreq.150.times.10.sup.9/l;
WBC.gtoreq.4.times.10.sup.9/l; PTT within normal range of
institution; adequate renal function: serum creatinine and BUN
within 2.times. the upper limit of normal (ULN) institution;
adequate liver function: serum bilirubin .ltoreq.1.5 mg/dl;
SGOT/ALT, SGPT/AST, and alkaline phosphatase within 2.times.ULN of
institution; written informed consent; and ability to return for
all study visits.
[0127] Exclusion Criteria: Patients were not eligible for the study
if any of the following criteria were present in the study eye or
systemically: patients scheduled to receive, or have received any
prior Photodynamic Therapy with Visudyne; significant media
opacities, including cataract, which might interfere with visual
acuity, assessment of toxicity or fundus photography; presence of
other causes of choroidal neovascularization, including pathologic
myopia (spherical equivalent of -8 diopters or more negative), the
ocular histoplasmosis syndrome, angioid streaks, choroidal rupture
and multifocal choroiditis; patients in whom additional laser
treatment for choroidal neovascularization might be indicated or
considered; any intraocular surgery within 3 months of study entry;
previous vitrectomy; previous or concomitant therapy with another
investigational agent to treat AMD except multivitamins and trace
minerals; previous radiation to the fellow eye with photons or
protons; known allergies to the fluorescein dye used in angiography
or to the components of EYE001 formulation; any of the following
underlying systemic diseases including: uncontrolled diabetes
mellitus or presence of diabetic retinopathy, cardiac disease:
myocardial infarction within 12 months prior to study entry, and/or
coronary disease associated with clinical symptoms, and/or
indications of ischemia noted on ECG, impaired renal or hepatic
function, stroke (within 12 months of study entry), active
infection, active bleeding disorders, any major surgical procedure
within one month of study entry, active peptic ulcer disease with
bleeding within 6 months of study entry; concomitant systemic
therapy with corticosteroids (e.g. oral prednisone), or other
anti-angiogenic drugs (e.g. thalidomide); previous radiation to the
head and neck; any treatment with an investigational agent in the
past 60 days for any condition; any diagnosis of cancer in the past
5 years, with the exception of basal or squamous cell
carcinoma.
[0128] Study Medication.
[0129] Drug Supply
[0130] EYE001 was used as the anti-VEGF therapy in this study.
EYE001 drug substance is a pegylated anti-VEGF aptamer. It was
formulated in phosphate buffered saline at pH 5-7. Sodium hydroxide
or hydrochloric acid may be added for pH adjustment.
[0131] EYE001 was formulated at three different concentrations: 3
mg/100 ul, 2 mg/100 ul and 1 mg/100 ul packaged in a sterile 1 ml,
USP Type I graduated glass syringe fitted with a sterile 27-gauge
needle. The drug product was preservative-free and intended for
single use by intravitreous injection only. The product was not
used if cloudy or particles were present.
[0132] The active ingredient was EYE001 Drug Substance, (Pegylated)
anti-VEGF aptamer, and 30 mg/ml, 20 mg/ml and 10 mg/ml
concentrations. The excipients were Sodium Chloride, USP; Sodium
Phosphate Monobasic, Monohydrate, USP; Sodium Phosphate Dibasic,
Heptahydrate, USP; Sodium Hydroxide, USP; Hydrochloric acid, USP;
and Water for injection, USP.
[0133] Dose and Administration
[0134] Preparation. The drug product was a ready-to-use sterile
solution provided in a single-use glass syringe. The syringe was
removed from refrigerated storage at least 30 minutes (but not
longer than 4 hours) prior to use to allow the solution to reach
room temperature. Administration of the syringe contents involved
attaching the threaded plastic plunger rod to the rubber stopper
inside the barrel of the syringe. The rubber end cap was then
removed to allow administration of the product.
[0135] Treatment Regimen and Duration. EYE001 was administered as a
100 .mu.l intravitreal injections on three occasions at 28 day
intervals. Patients were enrolled to receive 3 mg/injection. If 3
or more patients experienced Dose-Limiting Toxicity (DLT's), the
dose was reduced to 2 mg and further tolmg, if necessary, each in
an additional 10 patients.
[0136] PDT Administration.
[0137] PDT was given with EYEOO 1 only in cases with predominantly
classic CNV. The standard requirements and procedures for PDT
administration were used as described in Arch Ophthalmol 1999,
117:1329-1345. PDT was required to be given 5-10 days prior to
administration of the anti-VEGF aptamer.
[0138] Patient Enrollment.
[0139] Before recruitment of patients into the study, written
Institutional Review Board (IRB) approval of the protocol, and
informed consent form were obtained. Case report form screening
pages were completed by study site personnel. Patients who meet the
eligibility criteria and have provided written informed consent
were enrolled in the study.
[0140] Follow-Up Schedule.
[0141] Patients were clinically evaluated by the ophthalmologist
several days after injection and again one-month later just prior
to the next injection. ETDRS visual acuities, kodachrome
photography and fluorescein angiography were performed monthly for
the first 4 months.
[0142] Endpoints.
[0143] The safety parameters given under the DLT section above were
the primary endpoint of the studies. In addition, the percentage of
patients with stabilized (0 line change or better) or improved
vision at 3 months, the percentage of patients with a 3-line or
greater improvement at 3 months, and the need for PDT re-treatment
at 3 month as determined by the investigator were other endpoints
studied.
[0144] Results.
[0145] No serious related adverse events were noted for the 21
patients treated in this study. Two patients experienced serious
unrelated adverse events. One patient, an 86 year-old woman with a
long-standing history of peripheral vascular disease as well as
borderline hypertension and type II diabetes mellitus experienced 2
myocardial infarctions, the second of which was fatal. The first
event occurred 11 days following the first intraocular injection of
anti-VEGF aptamer. The second event occurred 16 days following the
third and last injection. The acute myocardial infarctions took
place approximately 2 months apart. These events were believed to
be unrelated to aptamer therapy by the investigator and systemic
levels of the drug are negligible based on pharmacokinetic data. A
second patient, a 76 year-old man with a 10-month history of
depression attempted suicide with ingestion of acetaminophen 11
days after the third and last dose of anti-VEGF aptamer. The
patient's mental condition improved. Treatment of the patient has
remained unchanged and the patient is presently followed in the
study.
[0146] Tables 1A-C show the unrelated or non-severe events reported
in these groups. In patients treated with the anti-VEGF aptamer
alone, ocular adverse events probably associated with
administration of the anti-VEGF aptamer included vitreous floaters
(4 Events), mild anterior chamber inflammation (3 Events), ocular
irritation (2 Events), increased intraocular pressure (1 Event),
intraocular air (1 Event), vitreous haze (1 Event), subconjunctival
hemorrhage (1 Event), eye pain (1 Event), lid edema/erythema (1
Event), dry eye (1 Event) and conjunctival injection (1 Event).
Events possibly related to administration of anti-VEGF aptamer
included, asteroid hyalosis (1 Event), abnormal vision (1 Event)
and fatigue (1 Event). Events termed unrelated to administration of
anti-VEGF aptamer included headache (1 Event) and weakness (1
Event). In patients treated with the anti-VEGF aptamer and PDT
adverse events probably associated with this combination of therapy
included ptosis (5 Events), mild anterior chamber inflammation (4
Events), corneal abrasion (3 Events), eye pain (3 Events), foreign
body sensation (2 Events), chemosis (1 Event), subconjunctival
hemorrhage (1 Event) and vitreous prolapse (1 Event). Events
possibly related to combination therapy included fatigue (2
Events). Events unrelated to combination therapy included pigment
epithelial detachment (1 Event), joint pain (1 Event), upper
respiratory infection (1 Event) and bladder infection (1 Event).
The increase in ptosis and corneal abrasion seen in the setting of
combination therapy may be related to the use of a contact lens in
association with PDT. Of note, all instances of anterior chamber
inflammation or vitreous haze were mild and transient in
nature.
1TABLE 1A Adverse events associated with administration of
anti-VEGF aptamer alone or in combination with PDT. Anti-VEGF
Anti-VEGF Aptamer Aptamer & N (%) PDT N (%) Adverse Event 10
Patients 11 Patients Ptosis 0 5 (45.4) Lid Edema/Erythema 1 (10) 2
(18.2) Conjunctival Injection 1 (10) 0 Chemosis 0 1 (9.1)
Subconjunctival Hemorrhage 1 (10) 1 (9.1) Dry Eye 1 (10) 0 Corneal
Abrasion 0 3 (27.3) Anterior Chamber 3 (30) 1+ Cells 4 (36.4) Trace
Inflammation Cells Trace Cells 1+ KP; Trace Cells Trace Cells Trace
Cells Trace Cells IOP Increase 1 (10) 0 Pupillary Abnormalities 0 0
Rubeosis 0 1 (9.1) Cataract 0 0 Vitreous Haze 1 (10) 2 (18.2)
Vitreous Prolapse 0 1 (9.1) Vitreous Floaters 4 (40) 0 Asteroid
Hyalosis 1 (10) 0 Intraocular Air 1 (10) 0 Peripapillary Hemorrhage
0 1 (9.1) Pigment Epithelial 0 1 (9.1) Detachment Abnormal Vision 1
(10) 0 Photopsia 1 (10) 0 Foreign Body Sensation 1 (10) 2 (18.2)
Eye Pain 1 (10) 3 (27.3) Blepharospasm 0 1 (9.1) Ocular Irritation
2 (20) 1 (9.1) Ocular Tenderness 0 1 (9.1) Ocular Pruritis 1 (10) 0
Tearing 1 (10) 0 Headache 1 (10) 0 Rhinorrhea 0 1 (9.1) Fatigue 1
(10) 2 (18.2) Weakness 1 (10) 0 Joint Pain 0 1 (9.1) Upper
Respiratory Infection 0 1 (9.1) Bladder Infection 0 1 (9.1)
[0147]
2TABLE 1B Adverse events associated with administration of
anti-VEGF aptamer alone. Anti-VEGF Aptamer N Adverse Event
Relationship 10 Patients Probably: Vitreous Floaters 4 Anterior
Chamber Inflammation 3 Ocular Irritation 2 Vitreous Haze 1
Increased Intraocular Pressure 1 Intraocular Air 1 Subconjunctival
Hemorrhage 1 Conjunctival Injection 1 Eye Pain 1 Lid Edema/Erythema
1 Dry Eye 1 Possibly: Asteroid Hyalosis 1 Abnormal Vision 1 Fatigue
1 Unrelated: Headache 1 Weakness 1
[0148]
3TABLE 1C Adverse events associated with administration of
anti-VEGF aptamer and PDT. Anti-VEGF Aptamer & PDT N Adverse
Event Relationship 11 Patients Probably: Ptosis 5 Anterior Chamber
Inflammation 4 Corneal Abrasion 3 Eye Pain 3 Foreign Body Sensation
2 Chemosis 1 Subconjunctival Hemorrhage 1 Vitreous Prolapse 1
Possibly: Fatigue 2 Unrelated: Pigment Epithelial Detachment 1
Joint Pain 1 Upper Respiratory Infection 1 Bladder Infection 1
[0149] Two patients elected to prematurely terminate their
participation in the study. One patient believed that her vision
was not improving and did not want further injections. The other
patient had depression and transportation problems. Both patients
withdrew their consent prior to the third and last injection of the
aptamer. Visual acuity in both patients remained stable throughout
their participation in the study. A third patient died prior to the
final visit.
[0150] No dose decrease was required for any patients in the study.
Review of color photographs and fluorescein angiograms of these
patients revealed no signs of retinal vascular or choroidal
toxicity.
[0151] Of those patients (N=8) who completed the 3-month treatment
regimen of the anti-VEGF aptamer alone 87.5% had stabilized or
improved vision and 25.0% had a 3-line improvement of vision on the
ETDRS chart at 3 months (See Table 2).
4TABLE 2 Visual data of patients with subfoveal CNV treated with
anti-VEGF aptamer alone. .+-.No of Patient Lines At # Baseline Day
8 Day 29 Day 57 Day 85 Day 85 03-001 20/50 20/40 20/40 20/32 20/32
+2 04-001 20/125 20/64 20/80 20/80 20/80 +2 06-001 20/160 20/125
20/100 20/125 OUT +1 07-001 20/100 20/100 20/64 20/80 20/80 +1
07-002 20/320 20/80 20/64 20/64 20/50 +8 08-001 20/125 20/125
20/100 20/100 20/160 -1 09-001 20/500 20/200 20/400 20/320 OUT +2
(Day 36) 10-001 20/500 20/640 20/500 20/400 20/500 0 10-002 20/200
20/125 20/160 20/160 20/160 +1 10-003 20/400 20/160 20/160 20/160
20/126 +5
[0152]
5 CHANGE IN VISION AT 3 MONTHS Stabilized or .gtoreq.3 Line
Improved Improvement EYE001 87.5% 25.0% Treated - (N = 8) which
represents all eyes that completed the protocol.
[0153] Eleven patients were treated with both the anti-VEGF aptamer
and PDT. In this group of patients (N=10) who completed the 3-month
treatment regimen, 90% had stabilized or improved vision and 60%
showed a 3-line improvement of vision on the ETDRS chart at 3
months (Table 3). These 3-line improvements included gains of +3,
+5, +4, +4, +6, and +3 ETDRS lines of vision.
6TABLE 3 Visual data of patients with subfoveal CNV treated with
anti-VEGF aptamer combined with PDT. .+-.No of Lines Re- At latest
Patient Base- peat time- # line Day 8 Day 29 Day 57 Day 85 PDT
point 06-011 20/400 20/320 20/100 20/640 20/200 NO +3 06-012 20/250
20/160 20/125 20/125 20/80 NO +5 08-011 20/40 20/32 20/20 20/20
20/26 YES +2 10-011 20/160 20/160 20/160 20/160 OUT NO 0 05-011
20/100 20/64 20/64 20/64 20/40 NO +4 12-011 20/160 20/100 20/250
20/200 20/200 NO -1 06-013 20/800 20/640 20/800 20/800 20/320 YES
+4 02-011 20/500 20/200 20/160 20/80 20/126 YES +6 06-014 20/100
20/80 20/80 20/80 20/100 NO 0 06-015 20/125 20/40 20/64 20/50 20/80
NO +2 02-012 20/500 20/500 20/125 20/320 20/250 YES +3
[0154]
7 CHANGE IN VISION AT 3 MONTHS Stabilized or .gtoreq.3 Line
Improved Improvement EYE001 90% 60% Treated - (N = 10) which
represents all eyes that completed the protocol.
[0155] Of the remaining patients who did not show a 3-line gain,
only one showed a loss of vision at 3 months and this patient lost
only one line of vision at this time point. No patient in this
group lost more than one line of vision at 3 months.
[0156] Repeat PDT treatment at 3 months (whose need was solely
determined by the investigator) was performed in 4 of 10 eyes (40%)
that participated for the complete duration of the study.
OTHER EMBODIMENTS
[0157] Although the present invention has been described with
reference to preferred embodiments, one skilled in the art can
easily ascertain its essential characteristics and without
departing from the spirit and scope thereof, can make various
changes and modifications of the invention to adapt it to various
usages and conditions. Those skilled in the art will recognize or
be able to ascertain using no more than routine experimentation,
many equivalents to the specific embodiments of the invention
described herein. Such equivalents are intended to be encompassed
in the scope of the present invention.
[0158] All publications, patents, and patent applications mentioned
in this specification are herein incorporated by reference.
* * * * *